Electrolytic apparatus for the manufacture of nitrocellulose.



GELLULOSE.

ELECTROLYTIC APPARATUS FOR THE MANUFACTURE OF NITRO APPLICIATION FILED MAR. 10, 1906.

I \NVENTQ kiziiw 1 GASTON CHANDON DE BRIAILLES, OF PARIS, FRANCE.

ELECTROLYTIC APPARATUS FOR THE MANUFACTURE OF NITROCELLULOSE.

Specification of Letters Patent. Application filed March 10,1906. Serial No. 305.346.

Patented Dec. 24, 1907.

To all whom it may concern:

Be it known that I, GASTON CHANDON DE BRIAILLES, gentleman, citizen of the French Republic, residing ment of the Seine, France, have invente' certain new and useful Improvements in Electrolytic Apparatus for the Manufacture of Nitrocellulose, of which the following is a specification.

In the manufacture of nitrocellulose for the manufacture of smokeless powder for erally these are added-to other quantities of these acids in a state ofconcentration, which increases the net cost and indefinitely increasesthe volume of liquid employed. In this electrolytic concentrationof of manipulation are avoided, also'all losses by hydration by damp air and the same acids can be ,used almost indefinitely save" that part of the nitric acid passing into combination with the nitrated cotton.

The accompanying drawing is a vertical section of a receptacle for nitrating cellulose.

Each receptacle employed is preferably 0 lindrical and formed of stren thened glass. he closure at the upper'part 1s effected by a glasscover or stopper. This reservoir is furnished at its convex base with a branch 8, and a glass delivery valve 9. Towards the middle of the hei ht of the reservoir onthe interior of the wal a circular projection 10, is provided, strong enough to; support a porcelain artition 11 erfor'ated with a number of holes 12, is htl ":heaped the cellulose 13, to be nitrate The reservoir is filled with a suitable mixture of concentrated sulfuric acid and ordinary nitric acid. a

A thermometer 14 is laced vertically in the chamber 15 formed in the lower part of the reservoir.- The reading of this and any at Paris, in the De art-' ed for this manufacture become unthe Upon" this partition other instrument employed in the operation and located within the receptacle can be made without any necessity of opening the reservoir. I 4

A gilded platinum ositive electrode 16 is arran ed against the ower face of the porcelain (iaphragm. In its inactive part it is isolated from the acids by a small glass tube which has been cast and soldered to the stem on the same metal conductor.

The platinum'negative electrode '17 rests on the bottom of thereservoir at the part where the density of the nitric acid is-lowest. The electrodes are platinum or gilded platinum wire drawn out. They thus constitute rheostats to moderately heat the liquid. The active surface of the negative electrode ought to be smaller than that of the positive electrode so that the. quantity of nitric acid involved will be the least possible.

In order to obtain a good nitration of the cellulose, it is necessary to have in solution a small uantity of nitrous acid, which is produced y the action of the hydrogen in contact with the negative electrode and the nitric acid. An excess of nitrous acid can be detected by the coloration imparted to the colorless liquid mass. In this case the surface of the'negative electrode ought to be reduced or it ought to be enveloped with asbestos cloth or spun lass which reduces the diffusion of the' aci the occluded gases predominate. The immersed cellulose in the mixture of the two acids will be found to be nitrated in about 3 or 4 hours if the temperature does not fall below 30". C. In any case, it ought not to exceed 40 C. In order to moderate the heating action resulting from the passage of the current, the electric current consumption can be reduced, but this will reduce the speed of concentration.

The nitrated cellulose can be washed without'opening the receptacle and without allowing any deleterious gases to be liberated. To attain this result the exhausted liquid can be drawn oil by means of a suction acid pump attached to the delivery tube. Then y the aid of porcelain disk 18 forming a piston mounted on a neck of the same material adapted to engage in a flexible stopper 19 of india-rubber a strong force can be exercised on the cellulosein order to expel the absorbed acids. When one has drawn off by the ump all the liquid which passes by the de ivery tube, water is fed into the two chambers of s and makes the action of the receptacle, the nitrated cellulose is thus washed until it no longer evolves vapor. The receptacle is then opened and the cellulose is submitted to further washings in the acidsadded to a suitable quantit open air.

It is necessary before proceeding to a fresh operation to make the pump draw off all the 'washing water which adheres to the bottom and the walls and in case of need to flow back into the receptacle the air compressed by the pump. A fresh charge of cellulose to' be'nitrated is placed on the orcelain dia hragm, the receptacle is closed and the ex haus'ted nary nitric acid is delivered byt e pump. The current is switched on in order to' roduce the desired concentration. Anaci ometer may be used to indicate the degree to be attained. All the receptacles of the same installation are grouped in series and are traversed by the same current.

Having now particularly described and ascertained the nature of my said invention of ordi perforated diaphragm'dividing it into upper and lower chambers, a positive electrode lo.- cated adjacent to the underside of the diaphragm, and a negativeelectrode locates near the bottom of the receptacle.

' 3. The combination with a receptacle, of a perforated diaphragm dividing'it into u er and lower chambers, and electrodes of gil d ed platinum-wire located in the lower chamber.

' -4. The combination with a receptacle, of a perforated diaphragm dividing it into upper and lower chambers, wire electrodes in the lower chamber, and a piston normally placed at the top ofthe upper chamber, and means for operating said piston from outside of the receptacle.

5. The combination with a rece tacle, of means adapted to retain a charge 0 cellulose in the upper part of the same, means for conveying a current of electricity into the liquid contents of the lower part of said rece tacle,

and means for comlpressing the cellu ose toextract the liquid t erei'rom. In testimony whereof I have hereunto set my hand in presence of two subscribing wit- GASTOK CHANDON DE BRIAILLES.

Witnesses:

Eve. DAUMAS, Avrsn V. M. Rrnnn'r'r. 

